ARM: Add fixed PCI i/o mapping
This adds a fixed virtual mapping for PCI i/o addresses. The mapping is
located at the last 2MB of vmalloc region (0xfee00000-0xff000000). 2MB
is used to align with PMD size, but IO_SPACE_LIMIT is 1MB. The space
is reserved after .map_io and can be mapped at any time later with
pci_ioremap_io. Platforms which need early i/o mapping (e.g. for vga
console) can call pci_map_io_early in their .map_io function.
This has changed completely from the 1st implementation which only
supported creating the static mapping at .map_io.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: Russell King <linux@arm.linux.org.uk>
Acked-by: Nicolas Pitre <nico@linaro.org>
diff --git a/arch/arm/include/asm/io.h b/arch/arm/include/asm/io.h
index 815c669..8f4db67 100644
--- a/arch/arm/include/asm/io.h
+++ b/arch/arm/include/asm/io.h
@@ -113,11 +113,19 @@
#define __iowmb() do { } while (0)
#endif
+/* PCI fixed i/o mapping */
+#define PCI_IO_VIRT_BASE 0xfee00000
+
+extern int pci_ioremap_io(unsigned int offset, phys_addr_t phys_addr);
+
/*
* Now, pick up the machine-defined IO definitions
*/
#ifdef CONFIG_NEED_MACH_IO_H
#include <mach/io.h>
+#elif defined(CONFIG_PCI)
+#define IO_SPACE_LIMIT ((resource_size_t)0xfffff)
+#define __io(a) __typesafe_io(PCI_IO_VIRT_BASE + ((a) & IO_SPACE_LIMIT))
#else
#define __io(a) __typesafe_io((a) & IO_SPACE_LIMIT)
#endif